Matt black will look sh!t! And I will guaranty you will see the lines from spraying with rattle cans.
Mk3 bonnets are cheap! Just buy one from eBay or something that is same colour.
If I saw it with a matt black bonnet I would think, what a tool! He's ruined the look of the mk3 and it now looks like a chav car.
Thing is, an ebay bonnet will most likely be just as chipped/scratched, so no point! 
As Khare said, most bonnets are just as bad second hand... And cant seem to even find one in my colour anyway

Scrappy/ebay bonnets will require same amount of painting as the one is have as well....
I was worried it could possibly look chavy though... And for streaks, i wouldnt rattle can it. Have a compressor and a small touch up gun at work

Anyone got any pics of one done?